There are many known earth moving apparatuses or the like. Typical prior art earth moving equipment or excavators use a bucket or dipper assembly on the end of a movable arm which is used to scoop earthen material from horizontal or vertical faces. The bucket or dipper is normally provided with sharp teeth to provide a digging action against the surface being worked and further includes a cavity for collecting the material so removed. Once the earthen material is received within the dipper, the arm is typically moved to another location for transfer of the material. The material is usually discharged into a dump truck, onto a conveyor, or merely onto some other pile.
Many such power shovels include a heavy door which is pivotally mounted on a lower end of the dipper. A conventional mechanical latch mechanism secures the door in its closed position and, when released, allows the door to open. Conventional latch mechanisms typically include a trip wire or cable assembly which has one end adapted for control by a power shovel operator and another end connected to a moveable latch lever which is generally located beneath the dipper door. The latch lever is typically coupled to a slidable rod or latch bar which selectively engages a latch keeper extending downward from a front wall of the dipper body of the dipper. The dipper door is held closed when the latch bar is in engagement with the latch keeper. The dipper door is caused to open by tripping the trip cable which moves the latch lever which causes the latch bar to slide away from the latch keeper and disengage from the latch keeper, whereby the dipper door will open under its own weight plus the weight of any material contained within the dipper body. Normally, the door is thereafter closed by swinging the dipper in such a direction so as to cause the dipper door to move by inertia towards its closed position until the latch bar reengages the latch keeper as is conventionally known.
As generally known in the art, when the dipper door falls open or slams shut against the dipper body, the impact, if not dampened, can cause damage to the dipper door, dipper body and/or other components of the power shovel. As is commonly understood, devices for dampening the effect of the opening and the closing of a dipper door are typically referred to as snubbers. Many prior snubbers include clutch disk assemblies or brake disk assemblies.